Creating strip with "virtual" spacing?

Questions
1

Hi

I got a number of wall cabinets arranged like this, where I want to put some WLEDs under:

112cm width (67LEDs) ↔ 60 cm(space) ↔ 90 cm width (54 LEDs)

Now the plan is to feed to strips from the center space, and configure the 90cm strip to be reverse in order (in the config).

But when running effects, I want the system to behave just as if I had LED’s in the 60cm empty space as well (do not want to use/hide 36 leds, that cannot be seen).
Apparently the solution to this is to create a ledmap.json file … The 60cm space corresponds to 36 LEDs…

But how should the second (longer) strip be configured (in length) ? In the config it starts at LED 54, but do I set the length to 67 - or 67+36, in order for the effect to behave properly ?

Regards
Brian

2

So you have Strip - A with 67 LEDs on the left and Strip B with 54 LEDs on the right.
They have a 60cm gap between them.
You plan to feed them both from the center of the 60cm gap
You’re going to reverse the order of Strip A.

Do you plan on using 2 different GPIOs to feed the 2 strips?

I don’t understand what you’re trying to convey here.
Take a “Sweep” effect for example. If we start the effect from the middle of your setup, do you expect both right and left strings to start and stop at the same time while sweeping from the center to the outside edges? That would involve some timing issues, as your asking as shorter strip to use the same amount of effect time as the longer.

3

If you want to add gaps then that is what I would do .
In the output setting the total length should with an extra fake 36 leds.
So 67 +36 +54 . In your ledmap you would just add the 67 first ( with reversed order if you like) then
36 blank leds ( with -1 ) and then 54 leds . This should do what you want but I do not think adding the gap is necessary unless your aim is to have the effect delayed in the middle

4

How to map the “-1” (example for 4 led setup - where 2nd and 3rd led’s are “dummy”)?

Like:
{“map”:[ 0, 1, 2, 3, 0, -1, -1, 1]}

Or:
{“map”:[ 0, -1, -1, 3, 0, -1, -1, 1]}

5

Found another workaround - add the “empty” space as segment number 2 … Then segment 1 is one side of the cabinets, and segment 3 is the other side…
It takes up a GPIO pin, but that is a minor thing :wink:

6

Dummy ( fake ) leds number should not be listed in the map so it is the 2nd map with {“map”:[ 0, -1, -1, 3, 0, -1, -1, 1]}
For your workaround yes use an extra pin or make your first pin with extra 36 and should work the same way but extra pin is better .
If you like the result then might be post a short video of the same to pay it forward

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